george earned 80, 85 and 90 on the first three tests in his geography class. Beacuse he didnt have time to study, he decides to guess randomly on the final test. the test has ten true-false questions, each worth 10 points. what is the probability his final average is more than 85?​

answer: 1 + 1 = 11

step-by-step explanation:

, and

for

step-by-step explanation:

we can analyze the pattern at which the terms increase. let us denote , , , so that we can call

note the following:

the pattern: to get the next term value, we just add the next term number (e.g. 1st, 2nd, to the previous term value (term values are the given numbers in the question, 1, 3, 6, 10, 15,

from , to get to , we add

from , to get to , we add

etc.

we need to form a recursive formula, a formula that has the next term as a function of the previous term. so a possible recursive formula can be

, and for

sadsdda

step-by-step explanation: